Electric-wave amplifier.



R11. coLPmTs. ELECTRIC WAVE AMPLIFIER.

APPLIOA-TION FILED JAN. 3, 1914.

Patented 11911116, 1915.

i; 'run s'rafrns PATENT ortica.

EDWIN HENRY COLPITTS, 0F EAST. ORANGE, NEW JERSEY, ASSIGNOR T0 WESTERN-ELECTRIC COMPANY, or New vomi, N. Y., a CORPORATION or ILLINOIS.

ELECTRIC-WAVE AMPLIFIERJ lTo all whom t may Concern.'

Be it known that I, EDWIN HENRY CoL- rrr'rs, a subject of the King ofGreat Brltain, residing at East Orange, in the county of Essex and Stateof New Jersey, have in vented a certain new and useful Improvement inElectric-Wave Amplifiers, of which the following is a full, clear,concise, and exact description.

This invention relates to electric wave repeating apparatus andparticularly to the use of vacuum discharge repeaters as exemplified bythe so-called audion forl repeating and amplifying in an output-cir cuitwavesV of electric energy received in an input circuit. Its object .isto improve the quality of transmission by producing in the outputcircuit electric Waves free from distortion with respect to the in utwaves.

The invention is especially use? phone 'and telegraph service forrepeating and amplifying alternating. current waves of small magnitude.

The principal parts of an audion element or structure are a heatedfilament or other source of ionization, an anode usually called a plate,and an intermediate electrode usually called a grid. These arepreferably inclosed in an evacuated glass vessel. Characteristicfeatures of the audion are that-current can How in one direction only inthe ionized stream, and that the strength of current in the streamflowing from its source to the plate is modified by electrostaticlrather than by electromagnetic vforce as in some other types of gaseousrepeaters.

A simple arrangement for using a single audionelement as a repeater isas follows:

the output circuit is connected, one side to p the filament and theother to the plate. Re-

peating coils are preferably employedtothe input and output circuitsrespectively, and a battery is included in the output circuit in serieswith the primary winding of the output repeating coil. The audionrepeater as thus used, valthough a powerful amplifying agent, does notrepeat in the out ut circuit a perfect form reproductiony of t eelectric wave received in the input circuit. This is due to the factthat thev space between the filament and thegrid 'has unilateralconductivity. vWhen an "alternating ul in tele- Specltifm 0f LetttPft'ent Patented Feb. 16, 191.5. Application med Jannayaim.ser1a1Np.s1o,19e.

potential appliedl between the filamentV l'and the grid, current flowsduring that part o f each wave cycle in which the grid is positlve, butlittle or no current flows i-n this -circuit during the other part whenthe grid is negative. This unsymmetrical action results 1n a'certamamount of distortion in 'the output waves which is avoided, inaccordance-with this invention, by employing two audion elements, one'ofwhich operates to repeat the positive parts and the other 4the negative`parts of the input waves. Two

structurally separate elements of the'audion type may be employed or twosuch elements may be combinedin onestructure for this purpose. i

In the drawings Figure -1 represents a system of circuits including twoseparate audlon structures combmed 1n .accordance with the-invention;Fig.l 2 represents a system of circuits including two audion elementscombinedas a single structure and in such a way as to ut111z`eacommon-source of 1on1zat1on; Fig-3 represents a commercial telephoneline equipped with one re- The same reference characters are used todesignate like parts in the several gures.

Incoming and outgoing conductors to and from the repeating apparatus ofthis invention are represented in the-several views by the wires 1, 2terminating in the primary winding 3 of an input repeating coil 4, andthe Wires 5, 6 terminating in the secondary winding 7 of an outputrepeating coil 8 respectively. The secondary winding ofthe `repeatingcoil 4 is divided into two coils 9 and 10, and the primary winding ofthe repeating coil 8 is divided similarly into two coils 11 and 12. Twoaudion elements are combined and included in each of the cirvcluding theprimary coils 11 and 12 .of the cuits. They comprise two heatedfilaments p'eating coil windin repeating coil 8, has included in acommon 'portion of it a battery 21. In each of the systems, shown inFigs. 1 to 4, there are employed three classes of circuits exclusive ofthe incoming and outgoing line circuits. One is the circuit of theheated filaments fed by the battery 19; The second is the ldivided inputcircuit which includes the coils 9 and 1() of the repeating coil 4, thegrids 17 and 18 oppositely connected in said circuit, a portion oftheionized stream and the filament or filaments. The third is the dividedoutput circuit which in Fig. 1 includes in the common portion thebattery 21 'and in the .divided'p'ortions the heated filaments 13, 14,the ionized streams, the primary coils 11, 12 of the repeating coil 8.In Figs. 2,' 3 and 4 the single {ilanient 13 is in the common portion ofthis circuit.

In Fig. 3, a telephone line is represented in which one repeating set oftwo audion elements vmay be employed to provide for commercial two-Waytelephonic transmission between two stations 48 and 49. The circuitarrangement is vthe same as that of Figs. 1 and 2 except that theprimary winding 3 of the input'repeating coil 4 is divided into fourcoils, as shown, and its several coils are included serially in thetelephone line, while the secondary winding 7 ofy the output re-` 8 isplaced in bridge of the telephone line and connected symmetrically withrespect tg the several coils of the primary In Fig. 4 are shown tworepeating sets A and B to provide, in another way, for com'- mercialtwo-way service. The telephone line is divided and the two partsseparatelybalancedby networks 46 and 47, respectively. The' primaryWinding 3 of the inpu't repeat ing coil 4 of the repeater sets isdivided into four coils which are included serially in the telephoneline extending' between the telephone station 48 and the network 46. Inthe same way four coils of the primary winding 3l of the repeating coil4' of'- the other set B are included serially in the line extendingbetween th'e telephone station 49 and the network 47. In'th'e systemofFig. 4, telephonie currents generated at station 48 are 'repeated bythe set A and reproduced in tlie line to station' 49, while telephoniecurrents generated at station' 49' are likewise repeated by the set B'and' reproduced in the liiieuto station' 48.

The` operation isas' .followsz- Telephonie currents orl otherelctri'c'current waves iiiceived in the primary winding 3 of 'the inputi repeating coil 4, and reproduced by tliecoils V.a 1o of the' Scddaiywinding ih erssf in the 'o curse at die moment' when a wave' is thesecondary winding of' the anodes 15, 16, and

35';v The' plates' 15, 16

'incl 'ded 1n said output' circuiti, an

comprising divided 'ized stream' included ineach Voutput circuit, andelectrodes, one 1n each 'cmpr'siiig input and iiput circuit;Acanyinstantoftims,except' 4'tit'cr vacuum' discharge repeater elementsy passing the point of zero current flow, there will be positivepotential impressed on one of thegrids, say 17 ,y and a 4correspondingnegative potential impressed on the other grid, 18. As current can fowbetween the heated filament and the grid of either audion elementronlywhen the grid is at positive potential with respect to the filament, theeffecton' the current in the ionized stream flowingbetween the filamentand plate will be different in the two audion' elements. The grid, which.is :for the moment positive, will materially alter the flow of .currentin the stream -in which grid, which at the same moment is negative,

ywill have little or no effect. Afs the electric current 'waveprogresses in the input circuit, the potential conditions on th'e1 twogrids become reversed so that the negative portion' of the wave(assuming the other portionconsidere'd to have been positive) willberepeated ldue to positive potential on the previously ineffectivegrid. Thus every variation in current produced by the input waves isrepeated by on'e or the other of the two audion elements.

Af suitable structure for the two audion elements when combined in oneis shownl in Figs. 3 and 4, wherein the -filz'unent 13 is supported fromone end of the glass bulb or vessel 34, the' leading-in wires to thelament b'eing connected to the tip and sleeve terminals respectively ofan ordinary lamp socket plug 44. The two' grids 17, 18 and two plates15, 16 are supported at the other end of the vessel and held in' theirproper positions by a'forked glass support 35. The upper ends of thegri'ds are attached by means of short wires 36, 37 to theupper ends ofthe support are centrally supported by' bo'w shaped: wires 38, 39respectively. liea'ding-in'wire's 40, 41, 42 and 43 are providedforconnecting the grids and plates in circuit, and the portions of'E thesewires on the inside of' trie 'vessel' port.

What is claimd is: v1'. electric wave-repeating apparatuscoinprising'divided'input' and divided output circuits, means forproducing two ionized: streams, said streamsbeing oppositely twoelectrodes for controlling said ionized streams respectively andoppositely connetted in said input circuit.

2.'- An' electricA wave repeating apparatus input' and divided outputIcircuits, means for producingv an iondivis'ionof said divisionof saidinput circuit for controlling' said'L ionized* streams respectively.

3; itin electric wavel repeating apparatus output' circuits and it isinterposed, but' the' 34 aid in their supoppositely connected in saidlcircuits, whereby 'the positive and. negative portions .of-

electric waves in said input.- circuit are repeated by said repeatertively in said output circuit.,A .A

` 4. In an electncwave repeating apparatus,'the combination withinputand output circuits, of two vacuumdischarge repeater elements oppositelyconnected in said circuits whereb'y one of said elements is adapted torepeat certain parts', and the other, the remaining parts of said inputwaves.

5, In an electric wave repeating apparay tus,'the combination of tworepeating elements comprising ionizing means, an anode and an inputelectrode or each said element, an `input repeating coil the secondarywinding of which is connected at anintermediate point to said ionizingmeans and at its opposite terminals to4 said input electrodesrespectively.

6. In an electric waverepeating appara-- tus, the combination of tworepeating elements comprising ionizing anode and an input electrode foreach said element,` an input repeating coil and an. out- 'put repeatingcoil, the secondary of, said input repeating coil divide elements4respec- Y,

, terminals of sai means and an and .the .di'visins ce 'etwa to Saidinput' electrodes respectively, and the primaryv repeating. elementsrespectively. .In an electric l wave repeating apparatus, 'thecombination with input and `output a0v winding of said Outputrepeatingcoil bein i divided and the divlsions connected to sai asl circuits anda repeating coil .in each-of .said l connected to saidanodes'respectively. I

In witness whereof,.I hereunto subscribe my name this 31st dayl of.December D.,

EDWIN HENRY COLIITIS.y Witnesses: u s

' NoNAisr E. TU'rnlLn,

Amon'IIAz r each said element, and two in- -circuits, of two repeatingelements together v I 'put electrodes res ectlvely, and the oppositeprimaryv Vwinding being:

